U.S. patent number 10,980,944 [Application Number 15/202,953] was granted by the patent office on 2021-04-20 for syringe tip cap.
This patent grant is currently assigned to Becton, Dickinson and Company. The grantee listed for this patent is Becton, Dickinson and Company. Invention is credited to Roger Groskopf, Charles G. Hwang.
United States Patent |
10,980,944 |
Hwang , et al. |
April 20, 2021 |
Syringe tip cap
Abstract
A tip cap is provided comprising a base portion having an upper
surface and a lower surface, a body having a top wall with a
non-circular cross-section extending from the upper surface, and a
shaft extending from the lower surface. A syringe assembly is
provided comprising a syringe comprising a barrel, and a syringe
tip, extending through the barrel and a connector provided on the
syringe tip. The syringe assembly further comprises a tip cap for
sealingly covering the syringe tip and comprising a base portion
having an upper surface and a lower surface, a body having a top
wall with a non-circular cross-section extending from the upper
surface, and a shaft extending from the lower surface having
connection means for attaching to the syringe tip.
Inventors: |
Hwang; Charles G. (Wellesley,
MA), Groskopf; Roger (Saddle Brook, NJ) |
Applicant: |
Name |
City |
State |
Country |
Type |
Becton, Dickinson and Company |
Franklin Lakes |
NJ |
US |
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Assignee: |
Becton, Dickinson and Company
(Franklin Lakes, NJ)
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Family
ID: |
1000005498024 |
Appl.
No.: |
15/202,953 |
Filed: |
July 6, 2016 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20160310671 A1 |
Oct 27, 2016 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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10691385 |
Oct 22, 2003 |
9415168 |
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29180313 |
Jul 27, 2004 |
D493526 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61M
5/3134 (20130101); A61M 2205/586 (20130101); A61M
2005/3104 (20130101) |
Current International
Class: |
A61M
5/31 (20060101) |
Field of
Search: |
;604/187 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Other References
Communication Pursuant to Article 96(2) EPC for European Patent
Application No. 03 773 313.6-1257 dated May 22, 2007 (6 pages).
cited by applicant.
|
Primary Examiner: Lee; Brandy S
Assistant Examiner: Hussain; Nidah M
Attorney, Agent or Firm: The Webb Law Firm
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. Utility application Ser.
No. 10/691,385, filed on Oct. 22, 2003, which is a
continuation-in-part of U.S. Design application No. 29/180,313,
filed on Apr. 22, 2003, which has issued as U.S. Design Pat. No.
D493526, the entirety of all of which are incorporated by reference
herein.
Claims
What is claimed is:
1. A tip cap comprising: a sealing base comprising a substantially
flat surface having an upper surface defining a plane and a lower
surface, a body having an elongated, non-circular shaped top wall,
said body extending from said upper surface in a first direction
with respect to the sealing base, said body having a non-circular
elliptical cross-section when viewed at an angle substantially
perpendicular to said upper surface, wherein the body of the tip
cap has a major axis and a minor axis, wherein the major axis and
the minor axis extend in a parallel direction with respect to the
sealing base, wherein the major axis is greater than the minor
axis, wherein an intersection of the major axis and minor axis
defines a rotational center point about which the tip cap rotates,
and wherein the non-circular shaped top wall allows a user to grasp
and apply a rotational force to the tip cap without having to
simultaneously provide a gripping force to the tip cap, and a shaft
extending from said lower surface, said shaft having a wall
defining a hollow portion and wherein the shaft includes an opening
at a bottom end, the shaft extending in a second direction with
respect to the sealing base and wherein the second direction is
opposite from the first direction.
2. The tip cap of claim 1, wherein said non-circular section is
comprised of a pair of arcuate structures.
3. The tip cap of claim 1, wherein said non-circular section is
comprised of a plurality of cylindrical structures arranged around
the central axis of said tip cap.
4. The tip cap of claim 1, wherein said top wall includes a
textured surface.
5. The tip cap of claim 4, wherein said textured surface includes a
plurality of dimples.
6. The tip cap of claim 1, wherein said shaft is joined to the
lower surface of the sealing base and is configured to cooperate
with a connector on a syringe to connect said tip cap to the
syringe.
7. The tip cap of claim 6, wherein said top wall is joined to the
upper surface of the sealing base and is configured to receive a
force imparted thereto to cause the tip cap to rotate with respect
to the syringe.
8. The tip cap of claim 1, wherein the top wall of the body is
coextensive with the sealing base of the tip cap along the major
axis of the body and wherein portions of the sealing base extend
radially outwardly with respect to the top wall along the minor
axis of the body, said portions of the sealing base extending
outwardly with respect to the top wall along the minor axis of the
body being configured to act as a shield against excessive downward
movement of a user's fingers relative to the tip cap.
9. The tip cap of claim 1, wherein said shaft is shaped internally
to releasably receive and contact a luer tip of a syringe and
shaped externally to cooperate with a connector on the syringe.
10. The tip cap of claim 1, wherein the elongated top wall is
configured to enable the user to grasp the tip cap at various
points at a predetermined distance from the rotational center point
measured along the major axis such that upon application of a
rotational force to the tip cap, the top wall acts as a lever arm
during rotation of the tip cap.
11. The tip cap of claim 1, wherein said body comprises a tubular
member having an open portion facing the first direction with
respect to the sealing base.
12. The tip cap of claim 1, wherein the hollow portion in the shaft
extending from said lower surface of the sealing base comprises a
well that is internally shaped to match a general shape of a
syringe tip or luer, said well having an inner end having a
generally flat profile and an external surface that is generally
conical and extending in the first direction with respect to the
sealing base.
13. A syringe assembly comprising: a syringe comprising a barrel
and a syringe tip extending from said barrel; and a tip cap for
sealingly covering said syringe tip and comprising: a sealing base
comprising a substantially flat surface having an upper surface
defining a plane and a lower surface, a body having an elongated,
non-circular shaped top wall, said body extending from said upper
surface in a first direction with respect to the sealing base, said
body having a non-circular cross-section when viewed at an angle
substantially perpendicular to said upper surface, wherein the body
of the tip cap has a major axis and a minor axis, wherein the major
axis and the minor axis extend in a parallel direction with respect
to the sealing base, wherein the major axis is greater than the
minor axis, wherein an intersection of the major axis and minor
axis defines a rotational center point about which the tip cap
rotates, and wherein the non-circular shaped top wall allows a user
to grasp and apply a rotational force to the tip cap without having
to simultaneously provide a gripping force to the tip cap, and a
shaft extending from said lower surface, said shaft extending in a
second direction with respect to the sealing base and wherein the
second direction is opposite from the first direction, said shaft
having connection means for attaching to said syringe tip.
14. The syringe assembly of claim 13, wherein the exterior of said
top wall further includes a textured surface.
15. The syringe assembly of claim 14, wherein said textured surface
includes a plurality of dimples.
16. The syringe assembly of claim 14, wherein said textured surface
includes a plurality of radially extended flanges.
17. The syringe assembly of claim 13, wherein a recessed well
extends at least partially through said lower surface of said base
portion.
18. The syringe assembly of claim 17, wherein, said syringe tip at
least partially extends into said well with said tip cap covering
said syringe tip of said syringe.
19. The syringe assembly of claim 13, wherein said non-circular
cross-section is rectangular.
20. The syringe assembly of claim 13, wherein said non-circular
section is comprised of a pair of arcuate structures.
21. The syringe assembly of claim 13, wherein said non-circular
section is polygonal.
22. The syringe assembly of claim 13, wherein said non-circular
section is comprised of a plurality of cylindrical structures
arranged around the central axis of said tip cap.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a tip cap for closure of the opening of a
liquid filled container, and more particularly, to a tip cap for a
syringe.
2. Description of Related Art
Conventional syringes include a barrel having an open proximal end
and an opposed distal end. A cylindrical wall extends between the
ends and defines a substance retaining chamber. A tip, sometimes
referred to as a luer, projects from the distal end of the syringe
barrel and includes a narrow passage, which communicates with the
substance-retaining chamber of the barrel. A plunger is inserted
into the open proximal end of the syringe barrel for sliding
fluid-tight engagement with the cylindrical chamber wall. Sliding
movement of the plunger in a distal direction urges fluid in the
chamber through the passage in the tip. Conversely, sliding
movement of the plunger in a proximal direction draws fluid through
the passage in the tip and into the chamber of the syringe
barrel.
Such syringes may further include a needle assembly with a needle
cannula having a proximal end, a pointed distal end and a lumen
extending axially therethrough. The needle assembly commonly
includes a hub which is securable to the syringe barrel for
selectively placing the lumen of the needle cannula in fluid
communication with the passage through the tip of the syringe
barrel. The needle assembly may be removably or fixedly mounted to
the tip of the syringe barrel.
Medications that are pre-filled into a syringe barrel must be
sealed to prevent contamination or loss of the medication prior to
use. Seals also prevent health care workers from being needlessly
exposed to medications. Where a needle is not staked to the syringe
body, the prior devices have included stoppers or closures mounted
over the tip at the distal end of the syringe barrel, referred to
as tip caps, to prevent leakage and to avoid contamination of the
medication. When a pre-filled syringe is capped with a tip cap, it
is especially important that a good seal be maintained. This is
usually achieved by tightly affixing the tip cap to the syringe.
However, when overly tightened the tip cap can be difficult to
remove or may be damaged. Furthermore, a pre-filled syringe may be
autoclaved after filling and capping to ensure a sterile package
for the contents. The autoclaving procedure however, can also have
the side effect of interactions between the tip cap to the syringe,
thereby further increasing the difficulty in removing the cap.
The prior art tip cap is removed from the syringe tip shortly prior
to usage of the syringe, and the hub of the needle assembly is
securely engaged with the luer and/or luer collar or other mounting
means adjacent the exposed tip of the syringe barrel. For example,
the needle hub may be threadedly engaged within a luer collar such
that the lumen of the needle cannula communicates with the exposed
tip of the syringe barrel, such as with the configuration sold by
the assignee herein under the trademark "Luer-Lok".
Current tip caps used to seal the liquid opening of the syringe
barrel, are typically a one-piece design having a circular cap wall
design. The mechanical advantage of a screw-type threaded cap is
translation of a rotational force to an axial force, resulting in
wedging the sealing mechanism of the tip cap onto the luer of the
container, and forming a tight seal due to the interference fit
between the sealing mechanism and the luer. With the current tip
caps, the torque required to attach and remove the tip cap is
generated when the user applies a gripping force to the outside of
the cap to rotate the cap on and off the syringe.
A problem associated with the prior art tip cap design has been the
user must apply a gripping force to grasp the circular cap by
exerting a force normal to the cap walls at the point of contact
with sufficient force to hold the cap from slipping, as well as
applying a twisting force (a torque) for rotating the cap about its
axis. This can be difficult for some users who lack dexterity or
strength especially considering the small size of the typical tip
cap or in the case where the tip cap is in excessively tight
engagement with the syringe barrel. The difficulty in using tip
caps according to prior art design is that the user must exert
forces on the tip cap at right angles to both grasp and rotate the
tip cap simultaneously.
A need exists, therefore, for an improved syringe tip cap where the
ability to attach and detach the tip cap is made easier by
providing a tip cap that is easier to grip while simultaneously
applying torque to rotate the tip cap. In particular, it would be
advantageous to provide a tip cap with a non-circular shaped
gripping surface that Provides the user with a surface to grip the
cap and apply force to the tip cap tangential to the axis of
rotation without having to also apply a gripping force.
SUMMARY OF THE INVENTION
In contrast to the prior devices discussed above, it has been found
that a tip cap which provides the user with enhanced mechanical
advantage for rotating the cap in order to affix it to a syringe
can be constructed in accordance with the present invention.
Specifically, the tip cap of the present invention includes a
non-circular cross-sectional shape that provides a gripping surface
for providing the user with extra leverage to rotate the cap.
The present invention provides a syringe tip cap assembly for
closing a syringe such as a pre-filled syringe barrel. The tip cap
includes a tip cap body having a non-circular top wall, a base
sealing surface and a depending shaft, which may be threaded, for
attachment of the tip cap to a syringe. The opening and closing of
a threaded tip cap is accomplished by imparting torque to the cap
tangential to the axis of rotation to cause the cap to rotate and
thereby open or close by engaging the helical threads of the cap
and container to raise or lower the cap. The force imparted to the
cap is applied by the user by gripping the perimeter of the
cap.
The tip cap of the present invention makes it easier and more
effective for the user to apply the rotational force needed to turn
the cap and thus open and close it. The non-circular shaped
gripping area provides a surface for the application of force
directly tangential to the axis or rotation of the cap. The force
is applied to the tip cap tangential to the axis of rotation at a
distance from the axis. Therefore, the non-circular tip cap acts as
a lever arm to multiply the force applied to the tip cap. In
addition, because of the non-circular shape, the user need not
apply a normal force to the sides of the cap in order to grip the
cap as is the case with prior art designs.
An advantage of the tip cap of the present invention is that it
provides the user with increased mechanical advantage for rotating
the cap.
Another advantage of the tip cap of the present invention is that
the outer surface of the tip cap contains features to enhance
handling and grip for the user, and to provide a comfortable
gripping surface that will not cut into the users fingers.
The present invention is therefore directed to a tip cap comprising
a base portion having an upper surface and a lower surface, a body
having a top wall with a non-circular cross-section extending from
the upper surface, and a hollow shaft extending from the lower
surface, attaching to a syringe barrel.
BRIEF DESCRIPTION OF THE DRAWINGS
The various features, objects, benefits, and advantages of the
present invention will become more apparent upon reading the
following detailed description of the preferred embodiment(s) along
with the appended claims in conjunction with the drawings, wherein
like reference numerals identify like components throughout,
and:
FIG. 1 is a perspective view of a tip cap according to an
embodiment of the present invention;
FIG. 2 is a first side view of the tip cap of FIG. 1;
FIG. 3 is a second side view of the tip cap of FIG. 1;
FIG. 4 is top view of the tip cap of FIG. 1;
FIGS. 4a and 4b are a cross-sectional views of the tip cap
according to the present invention along sections lines 4a-4a and
4b-4b of FIG. 4.
FIG. 5 is bottom view of the tip cap of FIG. 1;
FIGS. 6 and 6a respectively are perspective views of a tip cap
according to different embodiments of the present invention with a
textured top wall;
FIG. 7 is top view of the tip cap of FIG. 6;
FIG. 8 is a force diagram for the rotation of a tip cap according
to a prior art design;
FIG. 9 is a force diagram for the rotation of a tip cap according
to the present invention; and
FIGS. 10a-10f are perspective views of various alternate
embodiments of the present invention incorporating gripping
elements.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings, FIG. 1 shows a tip cap according to
the present invention. In particular, FIG. 1 shows a tip cap 10. As
can be seen, tip cap 10 includes a cap body 12 having a top wall 14
and a depending sealing base 16, and further includes a shaft 18
for connecting to and disconnecting from a syringe 200. The shaft
18 and the cap body 12 form a single unitary tip cap for receiving
a force imparted to the top wall 14 which causes the tip cap 10 to
rotate and connect to a syringe body. The top wall 14 is a
non-circular tubular structure, extending upwardly, or in a first
direction, from the sealing base 16. The sealing base 16 is a
substantially flat surface having an upper surface 16a defining a
plane and lower surface 16b. Top wall 14 is rigidly joined to the
upper surface 16a, preferably about at least the majority of its
perimeter, and the shaft 18 is rigidly joined to the lower surface
16b.
FIG. 2 depicts the tip cap 10 according to the present invention as
viewed from the side along a major axis 40 of the cap body 12. As
seen in FIG. 2, the top wall 14 is preferably coextensive with the
sealing base 16 along major axis 40 of the cap body 12. Also shown
is the shaft 18 extending downwardly, or in a second direction,
from the sealing base 16. The shaft 18 is configured to attach to
the luer tip 220 of a syringe 200. A connector 230 may be provided
at the tip 220 of the syringe 200 such as, for example, a luer
locking collar. The connector 230 may include internally defined
threads 232 extending from wall portion 234. Preferably, the shaft
18 has threads 20 for engaging complementary threads 232 of the
connector 230. The threads 20 are arranged to provide adequate
locking for a given angular displacement of the tip cap 10. With
this arrangement a seal is defined about the luer tip 220 by tight
contact with the interior of the shaft 18. The threads 20 can be
configured to cooperate with any known threaded configuration and
provide additional holding force to maintain the position of the
tip cap 10 relative to the luer tip 220. Alternatively, the shaft
18 may be configured with any other known connection configuration,
including, but not limited to, a slip luer connection.
FIG. 3 depicts the tip cap 10 according to the present invention as
viewed from the side along minor axis 42 of the tip cap body 12.
Preferably, as seen in FIG. 3, portions 16c of the sealing base 16
extend radially outwardly along the minor axis 42 of the top wall
14. The portions 16c may act as shields against excessive downward
movement of a user's fingers relative to the tip cap 10. With the
portions 16c, inadvertent contact with an associated syringe body,
particularly a portion that has been sterilized, can be
avoided.
FIG. 4 depicts the tip cap 10 according to the present invention as
viewed from the top (i.e., substantially perpendicular to the plane
defined by the upper surface 16a). In this view, the substantially
non-circularity of the top wall 14 is shown. Thus, a
cross-sectional view taken along a plane that is substantially
parallel to the plane defined by the upper surface 16a will be
substantially con-circular. Preferably, the top wall 14 is
elongated, having the major axis 40 and the minor axis 42. The top
wall 14, according to the present invention, will preferably be
formed in a non-circular elliptical shape, thereby providing an
elongated gripping surface 50 defined by the top wall 14. The
gripping surface 50 (see, e.g., FIG. 2) need not be limited to the
surface defined along the major axis 40, but can include the
surface defined along the minor axis 42. In addition, the gripping
surface 50 may include a surface that extends along both the major
and minor axes 40, 42. As will be described with reference to FIG.
9, the non-circular shaped top wall 14 allows a user to grasp the
tip cap 10 and apply a rotational force (torque) to the tip cap 10,
without having to simultaneously provide a tight grip on the tip
cap 10. In addition, with the non-circular shaped top wall 14 of
the present invention, the tip cap 10 is unable to roll away from a
user, as is often the case with circularly shaped prior art tip
caps.
FIGS. 4a and 4b depict cross-sectional views of the tip cap
according to the present invention along section lines 4a-4a and
4b-4b of FIG. 4. As shown in cross sections 4a-4a and 4b-4b, shaft
18 is preferably hollow having inner and outer walls 54 and 56,
respectively, to define a hollow portion, and being open or having
an opening, as generally shown by 57, at the bottom end 18b of the
shaft 18. Preferably, a well 58 is defined to at least partially
extend through the sealing base 16 shaped and configured to receive
a luer tip which would extend through the opening 57 and into the
well 58 and beyond the bottom face 16b with the tip cap 10 being
mounted to the syringe 200, as depicted in FIG. 2. The well 58 may
be shaped internally to match the general shape of the tip or luer.
For example, as shown in FIG. 4a, the inner end 59 of well 58 has a
flat profile, complementary to that of the part of the syringe to
which it is secured. External surface 44 of the well 58 can be
generally conical, as shown to advantageously be relied upon in
releasing the product from a mold. Also shown are depressions 52
recessed into the bottom face 16b.
FIG. 5 depicts a bottom view of the tip cap 10 according to the
present invention. Shown in FIG. 5 is the bottom face 16b of
sealing base 16. To facilitate removal of the tip cap 10 from a
molding machine, one or more depressions 52 may be recessed into
the sealing base 16, such as shown, recessed into the bottom face
16b.
It should also be noted that one or more outwardly extending nubs
or tabs 51 may be formed extending in cantilevered fashion from the
edge of sealing base 16 to facilitate handling of the tip cap 10
according to the present invention by machinery. The nubs or tabs
51 allow machinery, such as "forgiving" machines to handle the tip
cap 10 without engaging the gripping surface 50. Accordingly, a
more straightforward machine arrangement to engage nubs or tabs 51,
may be utilized than if the gripping surface 51 needed to be
handled. While four such nubs or tabs are shown in FIG. 5, it would
be understood by one skilled in the art to modify the number and
placement of such structures as needed.
As shown in FIGS. 6, 6a and 7, the tip cap 10 may have a textured
top wall 14. For example, the tip cap 10 depicted in FIG. 6
includes a plurality of ribs 60 on the exterior of the top wall 14.
The ribs 60 provide texture to the top wall 14 exterior surface in
order to provide the user with an enhanced gripping surface. As
will be apparent to one skilled in the art and from the disclosure
provided herein, the placement and number of ribs can be varied to
provide the user with the desired tactile sensation and grip
characteristics. In addition, while the surface texture in this
embodiment is shown as ribs, the surface of top wall 14 could
alternately have other types of textures or exterior structures to
provide tactile sensation and additional grip. As will be
recognized by those skilled in the art, and shown in FIG. 6a, the
top wall 14 could for example alternately have dimples or any other
known texture, including, but not limited to, the textures found in
a library maintained under the trademark "MOLD-TECH" by Standex
International Corp. of Salem, N.H., U.S.A.
Turning now to FIG. 7, the profile of ribs 60 can be seen.
Preferably, ribs 60 are located on the exterior of top wall 14
along the longer wall portions (disposed along the major axis 40).
In this way the ribs 60 are located where a user would grip the tip
cap 10 in order to rotate the tip cap. In addition, the ribs 60
further provide a surface that would not cut into the fingers of
the user. As seen in FIG. 7, the cross-sectional profile of the
body 12 of the tip cap 10 is elliptical with a plurality of grooves
62 defined in the gripping surface 50. Thus, the elliptical
gripping surface 50 is free of protrusions that would press into
the user's fingers under high torque on/off situations. Alternate
texture could also be located in the same location as depicted in
FIG. 7.
Turning now to FIG. 8, there is shown a force diagram that
illustrates the application of forces by a user to rotate a prior
art cap about its central axis. FIG. 8 shows a circular top wall 80
of a prior art tip cap, with the rotational center point 82 (i.e.,
the intersection of the major and minor axes (which, for prior art
devices are the same)) and which is being grasped by a user's hand
84. User's hand 84 is shown exerting a gripping force 86, normal to
the surface of the top wall 80. In order to rotate the cap the user
must also apply a rotational force (torque) to the tip cap. For
example, to rotate the tip cap in a clockwise direction, the user
would apply force 88 tangential to the top wall 80. Likewise, to
rotate the tip cap in a counterclockwise direction, the user would
apply force 89 tangential to the top wall 80 axis of rotation. The
amount of gripping force 86 the user must apply is proportional to
the rotational force needed to turn the tip cap. For example, a
user must grip the tip cap more tightly when turning a tip cap that
has been tightly closed as opposed to a tip cap that has been less
tightly closed.
In FIG. 9, there is shown a force diagram depicting the application
of force by a user to rotate the tip cap 10 according to the
present invention. FIG. 9 shows a top view of the tip cap 10
according to the present invention, depicting a non-circular top
wall 14 being grasped by a user's hand 92. The rotational center
point 92 (which is the intersection of the major and minor axes
(which, for the present invention are different)) is also shown. To
rotate the cap in a counter clockwise direction, the user would
apply forces 94 to the top wall 14. Likewise, to rotate the tip cap
in a clockwise direction, the user would apply forces 96 to the top
wall 14. In contrast to prior art designs, the user of the tip cap
10 according to the present invention merely applies a rotational
force to the tip cap 10 to threadedly engage or disengage the tip
cap; but a large gripping force is not required.
More particularly, a tip cap is opened or closed by imparting a
force to the tip cap sufficient to overcome the forces holding it
in place on the helical threads of the cap and the complementary
container, or other complementary connection configuration, whereby
the cap is moved from either an open or a closed position by the
rotation of the cap. The forces to rotate the threaded cap are
applied tangential to the axis of rotation of the cap at a distance
from the axis of rotation. As shown and described in FIG. 8, in
order to rotate a prior art circular cap, it must be grasped with
sufficient force to hold the cap, as well as rotate the cap about
its central axis. Thus, force must be applied tangential to the
axis of rotation to rotate the cap and normal to the cap surface to
grasp and hold the cap. The force applied to hold the cap, is
proportional to the rotational force applied thus making the
application of both a gripping and rotating force more difficult,
especially, for example when rotating a cap that is tightly
affixed.
In contrast, the tip cap 10 according to the present invention, has
an elongated gripping portion that provides the user with a lever
arm to easily rotate the tip cap 10. Preferably, as depicted in
FIG. 9, the user grasps the tip cap 10 at any points 98 on the top
wall 14 a distance "d" from the rotational center point 90 as
measured along the major axis 40. The forces 94 or 96 are exerted
directly on the top wall 14. The user need not grip the tip cap 10
to prevent slipping, because, unlike a circular tip cap, the
rotational forces (94 or 96) are exerted normal to the top wall 14
at the points 98. The top wall 14 acts as a lever arm of length "d"
to provide mechanical advantage to rotate the tip cap 10.
Rotational force may be used to remove the tip cap 10 even where a
threaded connector is not provided for a syringe body. For example,
the tip cap 10 can be twisted off of a luer to which it is mounted
with a slip luer connection. The torque advantage described above,
therefore, is as beneficial in this context, and similar contexts,
as well.
The tip cap 10 of the invention may be made of a clear molded
thermoplastic material so that the syringe tip may be readily
viewed through the tip cap. Representative materials include, for
example, polyethylene, polypropylene, and polyvinyl chloride.
Although it is within the purview of the invention to provide tip
caps which are transparent, it is also within the purview of this
invention to provide tip caps which are color coded.
While the tip cap 10 of the present invention has been particularly
described with respect to a preferred embodiment having a
non-circularly elliptical shaped top wall 14, it should be apparent
to one skilled in the art and from the disclosure provided herein
that various alternate embodiments of the tip cap top wall 14 are
contemplated by, and within the scope and spirit of the present
invention. For example, the tip cap 10 may alternately include
modifications such as alternate shapes or additional gripping
elements to enhance torque generation. Alternate top wall 14 shapes
can include, in addition to the non-circular elliptical shape of
the preferred embodiment, oval shapes, polygonal shapes, such as
squares and rectangles, and other non-circular shapes that provide
the desired torque-reducing characteristics of the tip cap 10 of
the present invention. Furthermore, additional alternate
embodiments may include the tip cap top wall 14 having radially
projecting structures arranged about the top wall 14. The
projecting structures provide the user with an extended gripping
surface 50, which acts as a lever arm to impart additional torque
to the tip cap 10 when rotated by the user, as described above in
connection with the embodiments of FIGS. 1-7 and 9.
The gripping elements may alternately be arranged in such a way as
to provide the user with an easily gripped surface for imparting
torque to the tip cap 10. The gripping element may take various
alternate forms, for example, the tip cap 10 may be made with a
star shape or having radially extending structures arranged around
the perimeter of the tip cap 10. Alternately, the tip cap 10 can be
shaped having a square or rectangular shape.
As will be recognized by one skilled in the art and from the
disclosure provided herein, various configurations are within the
scope and spirit of the present invention. By way of non-limiting
examples and turning to FIGS. 10a-f, alternate embodiments of the
tip cap 10 according to the present invention are shown. FIG. 10a
depicts an alternate embodiment wherein flanges 104 are positioned
adjacent top wall 14 to provide the user with an enlarged gripping
element, wherein the flanges extend outwardly from the top wall in
a radial direction to the edge of sealing base 16. It should be
noted however, that the dimension and size of the flanges can be
varied to provide the user with a surface of sufficient size to
apply force to rotate the tip cap. Preferable, the flanges 104 each
have a radial length extending outwardly greater that their
respective width extending in a circumferential direction.
Furthermore, additional flanges 104 could be utilized in a further
variation of the embodiment depicted in FIG. 10a. In addition, ribs
102 may also be provided with the embodiment of FIG. 10a, for
providing an additional gripping element.
FIG. 10b depicts a further alternate embodiment of the present
invention having two generally arcuate structures 108 protruding
from sealing base 16. The arcuate structures 108 are rigidly
connected together by support 110 that also extends from sealing
base 16. The structures 108 provide an easily gripped surface for
the user to impart torque to the tip cap 10. As further seen in
FIG. 10c, the shape and size of the arcuate structures 108 can be
varied to, for example, increase the size of the gripping surface.
The embodiments of FIGS. 10b and 10c do not have a receptacle
shaped cap gripping surface. For this reason these embodiments
resist the retention of moisture during a steam autoclave process.
In addition, they have the added advantage of not being subject to
a proclivity to nest one inside another when stored in bulk.
Turning now to FIG. 10d, a further alternate embodiment is depicted
having a central structure 112 extending from sealing base 16, with
a plurality of generally cylindrical structures 114 disposed about
the central structure 112 at preferably ninety-degree intervals,
for providing an easily gripped surface for the user to impart
torque to the tip cap 10. FIG. 10d may be modified in accordance
with the present invention by changing the number and spacing of
structures 114. In addition while structures 112 and 114 are
depicted as cylindrical, any other shape may be utilized, such as,
for example, polygonal.
FIG. 10e depicts a further alternate embodiment wherein the tip cap
14 according to the present invention has an increased diameter top
wall 14 with an undulating wall cross-section to provide a
plurality of ribs 120 circumferentially spaced about top wall 14
and interconnected by a rib webs 122 to provide the user with an
enhanced gripping surface by varying the angle of the surface that
the user grips. In that way, the user can hold a surface that is
not tangential to the rotational axis of the tip cap 10.
FIG. 10f depicts a further alternate embodiment wherein the tip cap
10 according to the present invention has a polygonal, rectangular
top wall. 14, to provide an easily gripped surface for the user to
impart torque to the tip cap 10. As will be apparent to one skilled
in the art, the dimension of the rectangular top wall can be varied
to, for example, increase the size of the gripping surface and
other polygonal configurations can be used. Furthermore, the
polygonal surface of the top wall 14, provides the user with a
surface to impart force perpendicular to the rotational axis
tangent.
While the preferred embodiments of the present invention have been
described so as to enable one skilled in the art to practice the
device of the present invention, it is to be understood that
variations and modifications may be employed without departing from
the concept and intent of the present invention as defined in the
following claims. For example, the top wall shape can be varied by
increasing or decreasing the major and minor axes. Alternately, the
top wall could be other non-circular shapes, which are preferably
elongated, such as, for example, rectangular. Accordingly, the
preceding description is intended to be exemplary and should not be
used to limit the scope of the invention. The scope of the
invention should be determined only by reference to the following
claims.
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